Controlling device.



' 0. E. CARPENTER.

CONTROLLING DEVICE.

APPLICATION FILED mm, 1907. Y 1 985,510. Patented Feb.'28,1911

WITNESSES: INVENTOR; W V I C zfl fzfli ar p zzz-i i (22M A. M

' I A ToRNEv UNITED STATES PATENT OFFICE.

CHARLES E. CARPENTER, {3E lUiI'W YQRK, N. Y., ASSIGNOR TO THE CUTLER-HAMMER MFG. 60., F MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

CQNTROLLING DEVICE.

Specification of Letters Patent.

Patented Feb. 28, 1911.

application filed May 9, 190?. Serial No. 372,738.

' ing, forming a part of this specification.

l invention relates to improvements in means for startingend controlling electric motors and particularlyio systems for auto maticall y controlling a motor or motors tor ope *ating pumps, compressors or the like.

in the preferredembodiment of my invention I provide means for zuitomatic-ally removing the resistance in the arnniture circult of the motor to cause the motor to operate atv one speed, other means for aniomatically inserting a 'stzmee in the field circult of the motor to cause the motor to o-per ate at' a second speed, and means operating under certain predetermined conditions to cause said first mentioned n'ieans to operate and operating under other conditions to cause said second mentioned means to operate.

Broadly considered, however, my invention contennplates resistance controlling means for causing the motor to operate in ditl crcnt ranges oi? speed, and means opcrah ing under varyii ig conditions for causing said resistance *ontrolling means to operate.

lleretofore in using electric motors for operating pumps or compressors it, has been necessary to use two or more pumps and motors, or to use one pump and one motor large enough to deliver a supply sutlicient tor "the i'naximum demand, and when using one large motor on the above conditions, an unusually large tank must, also be provided, as otherwise the motor would be constantly sh pping and starting with a normal demand on the tank. lly the provision of my sys tem, am enabled to supply a. greatly varying demand upon the tank, and am also enabled to use. a much. smaller tank than has heretofore been used This is particularly an advantageous feature in considering the first costof installing an apparatus, and also in considering the space'oceupied by tank.

For the purpose of disclosing my invention I have illustrated in the accompanying drawings one embodiment thereof.

in Figure l, I have shown a diagrammatic view of my invention illustrating the circuit arrangement thereof, and in Fig. 2 I have illustrated in detail one of the pressure gage switches.

in the embodiment of my invention illustrated, pressure is maintained in a tank 2 by a pump or compressor 3 operated by a motor 4. The operation of the motor is con trolled from pressure gages 5 and (S operating switches 7 and 8.

The armature 9 ol the motor is provided with av resistance 10 controlled by a starting device 11, provided with a. contact arm 12, controlled by a dash-pot- 13 and operated by a solenoid 14. The held 15 of the motor is provided with a resistance 16, cont-rolled by the lield resistance regulator 17. The resistance regulator is provided with a contactarm ll) controlled by a dash-pot and operated by a solenoid :21. The motor circuit is controlled by a switch 522 operated by a solenoid 23.

The form of pressure gage and switch illustrated in Fig. 2 comprises a casing 2i having arranged therein a diaphragm 25. @116 side of the diaphragm is provided with a rod 26 which projects through the casing and is provided with a knife edge, upon which rests an arm 28 at a point intermediate of its ends. The opposite side of the diaphragm forms, in connection with the using 24, a chamber 29 with which the tank 2- is connected by a suitable pipe 30. The arm 28 at its rear end engages under a knife pivot 31 secured in a bracket 32, suitably supported, and at. its opposite endhas mounted thereon a .fibcr extension 33, which carries a bridging contact. 34. A weight 35 is ad justably mounted on arm 28 to adjust. the pressure at which the switch shall operate. lft is obvious that. a variation in pressure in the tank 2 will cause the diaphragm to raise or lower the arm 28.

in operation we will assume that it is desired that the pressure in the tank 2 should not fall below 140 pounds and that it is desired to maintain the pressure as near as possible to between 150 and-160 pounds. The

COiltll l he adjusted to operate to close its;

when the pressure is 1.50 pounds, i l the 6 will be adjusted to'close switch i. s-airc hills to .llO pounds. 1 t icing new rat the pr ure in the tank lit; until it. 'iS lfitlpoundc-a, the pressure against the diaphragm 243 of the gage 3 will hcref-iirc be so reduced that the weight. on c arm thcreot will cause tihe outer end of 0 arm to drop and the bridge contacton e end thereof will bridge the contacts 36 i It circuit will therefore be estab: l troin one side 37 oi: the line by con through the arm 12, by C(Hi 1nd 351, thrt'iugh the winding of conductor 40, switch con- '1' when the p through the armature 9 of the motor, conductor 4-5, switch 22- andhy conductor a6 and 42 to the opposite side 43 of the line. Current also flows through the field windet the motor from conductor 3'1", by way 0. conductor 7, arm 19,, onducttn 48, field, to conductor l t the same time the molor circuit is closed, circuit. will also be closed from conductor 537, by conductor l9, tln'ough the winding of the solenoid 1 2, by tor 50 1| nd switch to conductor 46, energizing the solenoid which raises the arm rmtluallv cutting the resistance ll) out of the armature circuit and raising the niotor to its first speed. As soon as the arm 1-; moves ott' of the first 0|. the resistance contacts, a resistance 18 is inserted in circuit with the winding of the solenoid 23, which so reduces tl e strength thereof, that while 't will maintain the switch closed, it will not he sullicientilv strong to close the switch,

in event it opens. The motor will continue to run until the pressure in the tank 2 is raised sufficiently, when the pressnrc'in the chamber 29 will be correr pondingly raised, and the switch 8 will be opened, SlOPPlIlQ; the motor. l-low we will assume that while the motor is still operating, with all resistance cut out of the arn'iature circuit. the pressure in the tank falls below, say it) pounds, then the pressure in the gage U will hill to such an cv'tent that the arm of the switch 7 will drop and the switch 'i' will hrnlge the contacts 51 and This will close a circuit through the winding;- of the solenoid 21, from one side- 37 ot the line. by conductors 3?, t? and 54, through the winding" of the solenoid 2i, conductor 52-). switch T, conductors ell and 42, to the opposite side l of the line. The solenoid thus energized operates the arm 1!) to insert the resistance i l in the tield circuit and the motor 9 will perate at its second speed under a \vealteiuul s l l field. [is tin-.prcssurrincrea es to. say 1.7:)

poundrz the switch T will he opened, thus dt energizing the solenoid 2t. allowing the arm ill to drop, cutting out the field resistance 16, thereby strengthening the lield of the motor and thus slowing down the speed of the motor to the first, or glowspeed. It the pressure continues to rise to say use pounds the switch 8 will open and stop the motor.

It will be understood that 'lloatsor any other devices for operating the switch 7 and :3 may be used in (.onnection with my invention without' departing from the spirit thereof. ,t will also he understood that one I claim as new and desire to secure by Letters Patent, is:

1. In a system of control tor electric motors, the combination with a plurality of auijOllllLllClllly operated devices for starting the motor and causing the same to operate at different. speeds and means automatically.

operating under predctern'iincd conditions for causing the operation of one of said dov and. under other predctcrn'nncd condr tions for causing the operation of another of said devices to vary the speed of the motor.

In a system ofcontrol for electric motors, the combination with a plurality of electroresponsive devices for starting the motor and causing the same to operate at diti'crcnt; speeds and means automatically operated under predetermined conditions for causing the operation of one of said devices and under other predetermined conditions for causing the operation of the other of said devices to vary the speed of the motor.

3. The combination with a motor, of an electromagnetic device for regulating the armature speed thereof, a second electromagnetic. device tor regulating the licld thereof, a switch operating automatically under [H'Uh'l'tllllllllt'll conditions for conlro lling said armature regulating device and a second switch operating under prcdcteu mined conditions for controlling said licld regulating device.

4. A combinati n with a motor, ol resistance in arn'iaturc circuit tlicrcot, an electromagneticdevice 'l'or controlling said resistder predetermined conditions for controlling the operation of the field resistance controlling device.

The combination with the motor, of means for controlling the armature thereof, a second means for. controlling the field thereof, a switch controlling said armature controlling means, a pressure gage arranged to operate said switch when the pressure falls below predetermined point, a switch for controlling said field regulating device and a pressure gage arranged to operate said switch when the pressure falls below a second predetermined point.

G. The combination with a motor, of an armature resistance therefor, an electroniagnmeans for automatically removing said ari'nature resistance from circuit, afield resistance, an electro-magnetic means for automatically inserting said field resist ance in circuit, a switch operating automati-' cally under predetermined conditions for controlling said first mentioned elect-ro magnetic means and a second switch also operating automatically under predetermined conditions for controlling the operation of said second electromagnetic means.

7. The combination with a motor, of a resistance in the armature circuit thereof, an clectro inaguetic device for automatically removing said resistance from. circuit, a resistance in the field circuit thereof, an electromagnetic means for automatically inserting the field resistance in circuit, a switch for controlling said first mentioned means, a fluid pressure device for automatically operating said switch under redetermined conditions, a second switci for controlli'n the operation of said second inentione magnetic means and a. fluid pres sure device automatically operating under predetermined conditions for operating said second switch. I

8. In a motor controlling system, the combination with automatic means for starting the motor and causing the same to operv .itions for controlling .o operate at an V .o controlling eloci3ic c nzhination with means for actor to operate in a: plurality motors, causing a of speed ranges, of a fluid pressure de ice for operating said controlling means to cause the motorto operate at one speed,-and a second iinid pressure device for subsequently operating said controlling means to cause the motor to operate at an in--' creased Speed.

11. In a system of control for electric motors, the combination with an electromagnetically operated main switch, an armature resistance, an electromagneticall'y operated controlling member therefor, said. main switch being adapted, when closed, cause the operation of said member, a field resistance, an eleetromagnetically opera-ted controlling member therefor, a pressure actuated switch adanted to cause said main switch to close under predetermined coinditions, and another pressure actuated switch adapted to cause the operation of said field resistance controlling member under other predetermined conditions 12. In system of control for electric motors, the combination with an electromagnetically operated main switch, an armature resistance, an electromagnetically operated controlling member therefor, said main switch being adapted to control the operation of said cont-rolling member, a field resistance, an electromagnetically op erated controllii'ig member therefor, a pressure actuated switch adapted to cause said main switch to close under predetermined. conditions, another pressure switch adapted to cause the operation of said iield resistance controlling member under other predetermined conditions, and means for adjusting said switches to operate in a definite sequence to insure the removal of the arn'iature resistance from circuit prior to the insertion of the field resistance in circuit,

'13. In a system for controlling electric motors, the combination with motor of a plurality of means for causing the motor to operate at a plurality of speeds, and a fluid pressure mechanism operating under different predetermined conditions for operating said motor controlling means in a definite sequence to cause the r 'itor LU operate at any one of a numl'ier of different prodetermined speeds.

14. in a motor controlling syst in, the combination with. an electro-respoinsive device for causing the motor to operate at one speed, a second electro'responsive (let-ice fo causing the motor to operate at anoti speed, and a itiuid pressure inechanisn'i op ating unde predeterm ned conditio s automatically controll' the circuit tlurongzjn said clectro-rcsponsive cevices.

3.5. in a motor controllin h'ination, automatic mean motor to operate at one speed, aflI actuated 

